R: collapse dataframe with similar rows [duplicate]
Solution 1:
base R
Use aggregate and toString:
aggregate(Variable ~ Element, df, toString) #toString can be replaced by paste here
Element Variable
1 A Power, Current
2 B Power
dplyr
Use group_by and toString:
df %>%
group_by(Element) %>%
summarise(test = toString(Variable)) %>%
ungroup()
Data
df <- data.frame(Element = c('A', 'A', 'B'), Variable = c('Power', 'Current', 'Power'))